Test on Indica-compatibility of Candidate Indicacompatible Japonica Lines in Rice

[Objective] The aim was to breed the indica-compatible japonica lines（ICJLs）.[Method] The indica-compatibility of 5 candidate ICJLs were tested based on the pollen fertility and spikelet fertility of F1 hybrids with 6 indica testers,6 japonica testers and 6 middle testers.[Result] Candidate ICJL G2123,G2417,G2410 and G3005 were grouped into the exceptionally（Specific）indica-compatible lines based on their high indica-compatibility and low japonica-compatibility.Candidate ICJL G2615 was grouped into the non-compatible lines on their low indica-compatibility and low japonica-compatibility.[Conclusion] The testers,fertility identification standards,test methods of pollen fertility and spikelet fertility were discussed when the compatibility of CICJLs was tested.The reason of the indica-compatibility in G2417 was analyzed.

Flowering Characteristics of Japonica Rice Male Sterile Lines Adaptive to High Temperature and Summer Drought

[Objective] This study was conducted to screen japonica rice male sterile lines with good flowering characteristics under high temperature and summer drought. [Method] The flowering habits of 23 japonica male sterile lines, such as flowering peak, single-panicle flowering duration, single-plant flowering duration, en- closed glume rate, glume-opening angle, the distance between glumes, stigma exer- tion rate and sigma vitality, were compared with II-32A as a control under above weather condition. [Result] The flowering characteristics had significant difference a- mong the tested rice lines. Compared with the control, three japonica rice male ster- ile lines 35478A, 35489A and 35502A had better flowering traits, such as earlier flowering peak, longer single-panicle flowering duration, longer single-plant flowering duration, lower rate of enclosed glumes, larger glume angle and larger distance be- tween glumes. 35478A performed its flowering peak from 10：00-11：00 am, 1.5 h earlier than the control; 35489A exhibited higher stigma exertion rate, up to 76.23%; and 35502A had higher stigma vitality, up to 84.68%, which kept longer time than that of the CK. [Conclusion] The results will provide high-quality resources for the breeding of new japonica rice varieties with high-yield and high-temperature toler- ance.

Breeding and Application of Japonica CMS Line Yangfujing 7A with Fine Grain Quality, Disease Resistance and High Combining Ability in Rice

Yangfujing 7A, derived from the cross between Xu 9201A and Yangfujing 7 and its successive backcrosses, is a BT-type japonica CMS line developed by the Agricultural Institute of Riparian Region of Jiangsu Province. It shows good integrat- ed characteristics, stable male sterility, good flowering habits, high out crossing rate, strong disease resistance, fine grain quality （reaching the 1st class of national standards for fine quality rice） and high combining ability. In 2012, it was technically identified in Jiangsu Province. Its F1 hybrid combination Tongyoujingl （Yangfujing 7 A/R98）, showing high yield and good grain quality, was registered and released to commercial production by Jiangsu Crop Variety Appraisal Committee in 2013.

Genetic Improvement and Biological Characteristic Analysis of Dwarf Abortive TypeJaponicaCMS Lines with Wide Compatibility

From the view of methodology for genetic improvement ofJaponicacytoplasmic male sterile(CMS) lines,we introduced the breeding process of the dwarf-abortive type(DA type)JaponicaCMS line Chunjiang 95A with wide compatibility,and further investigated the biological characteristics of the DA type Chunjiang 95A and its isonuclear alloplasmic CMS line Dian-I type Chunjiang 95A.The results show that DA type Chunjiang 95A is a japonicalinous CMS line and mainly typical abortive,which is better in fertility stability than stained abortive typeJaponica CMS lines.The DA type Chunjiang 95A is featured with high stigma exsertion,good flowering habit,high outcrossing rate and wide compatibility.Its recoverability differs from stained abortive typeJaponicaCMS lines.Moreover,we discussed genetic improvement of the typical abortive type JaponicaCMS lines and the application prospects of heterosis.

Breeding of near-isogenic japonica rice lines with three major genes for resistance to bacterial blight

From 1986 to 1993, a set of near-isogenic japonicarice Iines with three major genes Xα-3, Xα - 4,and Xα-12 for resistance to bacterial blight(Xan-thomonas oryzae pv.oryzae)were developed anddesignated as CBB3, CBB4, and CBB12 respective-

粳型水稻三系雄性不育系竹稻08A的选育及应用

竹稻08A系福建省农业科学院水稻研究所育成的粳型三系不育系,于2023年通过福建省农作物品种审定委员会鉴定。该不育系不育性彻底,株叶形态好,抗倒性强,配合力好。本文介绍了不育系竹稻08A选育过程、主要生物学特性及所配制杂交水稻新品种的表现,以期为该不育系配组及推广应用提供参考。

日本鳗鲡心脏细胞系的建立及其在鳗鲡免疫应答研究中的应用

为建立稳定传代的鳗鲡细胞系用于鳗鲡免疫抗病机制的研究,研究利用组织块法建立了日本鳗鲡(Anguilla japonica)心脏细胞系(Anguilla japonica Heart cells,AJH)。AJH细胞在28℃、含20%胎牛血清(FBS)的DMEM/F-12培养基中培养,传代时间间隔3—4d,在第5代后更换为15%FBS传代培养。核糖体RNA基因分析显示细胞来源于日本鳗鲡。核型分析显示AJH细胞具有38条染色体,其中10条为中部着丝点染色体,10条为近中部着丝点染色体,18条为端着丝点染色体。病毒感染实验结果显示,鳗鲡疱疹病毒(Anguillad herpesvirus,AngHV)可在AJH细胞中增殖。利用多种试剂转染EGFP-AjLC3至AJH细胞,并通过流式细胞仪检测转染效率,结果显示AJH最高转染效率为(37.17±0.12)%。将AjIRF1真核表达质粒和AjIFNa、AjIFNc1启动子共转染至AJH细胞,利用双荧光素酶报告分析了过表达AjIRF1对AjIFN启动子荧光素酶活性的影响。结果显示AjIFNa和AjIFNc1启动子活性被显著上调,表明AJH细胞可用于体外的基因功能研究。经LPS刺激后,AJH细胞中AjTNF-α及AjIL-Iβ的表达水平明显上调;转染Poly I:C后,AJH细胞中AjRIG-Ia和AjRIG-Ib的表达水平明显上调,表明LPS和Poly I:C可诱导AJH细胞产生免疫应答。综上,研究所建立的日本鳗鲡心脏细胞系可为深入研究鳗鲡抗病毒、抗细菌免疫应答机制提供细胞实验模型。

Breeding and Application of a Japonic Rice Cytoplasmic Male Sterility Line, E-Jing A

The Chaling wild abortive type （CL-type） cytoplasmic male sterile line, E-Jing A, was characterized by stable sterility with a sterile plant percentage of 100%, a pollen sterile degree of 98% with dominated typical abortive pollens, and showed the characteristics of good outcrossing with a stigma exsertion rate of 48.2% and an outcrossing rate varied from 30% to 50%, good combining ability, and fine grain quality. E-Jing A was sensitive to temperature. Its duration from sowing to heading was 78-90 d when it was sown from mid May to early June at Wuhan. The breeding procedure of E-Jing A and its characteristics, relationship of restoring and maintaining were introduced.

Characterization of Reverse Thermo-sensitive Genic Male Sterile Lines in Cold Regions of China

Yannong S, a reverse thermo-sensitive genic male sterile （TGMS） line, is sterile at high temperature and fertile at low temperature. In the present study, the fertility of Yannong S and the japonica reverse TGMS lines derived from it was in- vestigated in Harbin, Heilongjiang from 2013 to 2015. The results showed that Yan- nong S was completely male sterile in July and August （the hottest months of the year in Harbin）, and the seed setting rate of bagged panicles was 0. We also in- ferred that the critical temperature for inducing the sterility of Yannong S was higher than 28 ℃. Most of the japonica reverse TGMS lines derived from Yannong S were completely aborted in July and August, with a seed setting rate of 0. It can be con- cluded that the reverse TGMS lines derived from Yannong S are genetically stable lines that have a long period of sterility in cold regions, so they may be the ideal genetic materials for the development and in-situ seed production of japonica hybrid rice.

Mining Applicable Elite Alleles of Growth Duration, Plant Height and Panicle Number per Plant by Conditional QTL Mapping in Japonica Rice

Unconditional and conditional QTL mapping were conducted for growth duration (GD), plant height (PH) and effective panicle number per plant (PN) using a recombinant inbred line (RIL) population derived from a cross between two japonica rice varieties Xiushui 79 and C Bao. The RIL population consisted of 254 lines was planted in two environments, Nanjing and Sihong, Jiangsu Province, China. Results showed that additive effects were major in all of QTLs for GD, PH and PN detected by the two methods, and the epistatic effects explained a small proportion of phenotypic variation. No interactions were detected between additive QTL and environment, and between epistatic QTL pairs and environment. After growth duration was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.71. When effective panicle number per plant was adjusted to an identical level, RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 4.64. After plant height was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.62, and RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 3.89. These applicable elite alleles could be used to improve target traits without influencing the other two traits.

Construction of SSR Linkage Map and Analysis of QTLs for Rolled Leaf in Japonica Rice

Genetic analysis of rolled leaf is important to rice ideotype breeding. To detect loci controlling rolled leaf of japonica restorer lines, SSR marker genotypes and phenotypes of flag leaf rolling index （LRI） were investigated in Xiushui 79 （P1, a japonica rice variety）, C Bao （P2, a japonica restorer line） and 254 recombinant inbred lines derived from the cross between P1 and P2 , and in two environments. A genetic map of this cross was constructed, QTLs for LRI were detected and their interactions with environments were analyzed. Among 818 pairs of SSR primers, 90 primers showed polymorphism between P1 and P2, and 12 markers showed highly significant correlation with LRI in both environments based on single marker regression analysis. The genetic map containing 74 information loci has a total distance of 744.6 cM, with an average of 10.1 cM between two adjacent loci. Three QTLs （qRL-1, qRL-7 and qRL-8-1） were detected with two softwares： WinQTLCart 2.5 and QTLNetwork2.0. qRL-8-1 was a new locus, accounting for 15.5% and 12.8% of phenotypic variations in the two environments, respectively. The phenotypic variation explained by additive effect was 6.6%. No interaction was found between qRL-8-1 genotype and environments.

Low-Temperature Response to Major Agronomic Traits by Using Recombinant Inbred Line(RIL) Populations Derived from Towada × Kunmingxiaobaigu

Development of the recombinant inbred line populations （RILs） is important basis to detect QTLs for cold tolerance at booting stage in rice. A set of 230 RILs derived from the cross of Towada and Kunmingxiaobaigu were used for evaluation of low-temperature response on major agronomic traits of plant height （PH）, panicle length （PL）, panicle exsertion （PE）, spikelet fertility （SF）, specific spikelet fertility （SSF）, and spikelets per panicle （SPP） under natural low-temperature growing environments in Yunnan Province, China. The results showed PH, PE, and SPP were mainly attributed by genotypes. PL was mainly influenced interactively by the genotypes × environments. SF and SSF were mainly controlled by the environments. Under the five different growth environments, F values of the six agronomic traits mentioned above ranged from 4.019 to 97.284. Significant difference was revealed between the lines. Under every environment, it indicated significantly positive correlation between SF and SSF, with correlation coefficients ranged from 0.826 to 0.885. It indicated significantly positive correlation between PH, PL, and PE. Under five different growing environments, variation coefficients of the six characters ordered in SSF （66.3%） 〉 PE （57.4%） 〉 SP （37.2%） 〉 SPP （16.2%） 〉 PH （9.6%） 〉 PL （6.4%）. SSF, PE and SF were most sensitive to low temperature stress at booting stage, while SPP, PH and PL being least. The RILs of Towada/ Kunmingxiaobaigu can be used as a genetic population to investigate cold tolerance at booting stage. SSF, PE and SF are most sensitive to cold tolerance at booting stage in rice. So far the the variation of PH, PL, and SPP related to cold tolerance are not clear under natural low-temperature environment. More tested environments and years are required to identify and evaluate cold tolerance at booting stage in rice.

粳型两系杂交水稻株高、穗部性状与产量性状比较分析

研究以新配制的48份粳型两系杂交稻组合及越光和盐丰47为试验材料,对粳型两系杂交稻杂交组合的株高、产量及穗部性状进行比较分析。试验结果表明:杂交稻新组合株高的差异较大,变化范围为98~129.0 cm,极差为31 cm。粳型两系杂交稻新组合穗部性状各指标均存在较明显差异,其中变异系数最大是单穗秕粒数,变异系数达74.04%。

Effect of Environment and Genetic Recombination on Subspecies and Economic Trait Differentiation in the F_2 and F_3 Generations from indicajaponica Hybridization

indica and japonica are the two most important subspecies of Asian cultivated rice. Identifying mechanisms responsible for population differentiation in these subspecies is important for indica-japonica hybridization breeding. In this study, subspecies and economic trait differentiation patterns were analyzed using morphological and molecular （InDel and Intron Length Polymorphism） data in F2 and F3 populations derived from indica-japonica hybridization. Populations were grown in Liaoning and Guangdong provinces, China, with F3 populations generated from F2 populations using bulk harvesting （BM） and single-seed descent methods （SSD）. Segregation distortion was detected in F3-BM populations, but not in F3- SSD or in F2 populations. Superior performance was observed with respect to economic traits in Liaoning compared with that in Guangdong and 1 000-grain weight （KW）, seed setting rate （SSR） and grain yield per plant （GYP） were significantly correlated with indica and japonica subspecies types. Analysis of molecular and morphological data demonstrated that the environment is the main factor giving rise to population differentiation in indica-japonica hybridization. In addition, we also found that KW, SSR and GYP are related to subspecies characteristics and kinship, which is possibly a significant factor resulting in economic trait differentiation and determining environmental adaptability. Our study has provided new insights into the process of population differentiation in these subspecies to inform indica-japonica hybridization breeding.

粳稻重组自交系的品质性状分析

以粳稻重组自交系为研究材料,对其糙米率、精米率、整精米率、垩白粒率、垩白度、白度、直链淀粉含量、蛋白质含量等品质性状进行了分析。结果表明,各品质性状都在重组自交系群体中都呈连续变异,且存在双向超亲分离现象。对品质性状进行相关性分析,结果显示在碾磨品质性状中,糙米率与精米率、整精米率呈显著正相关;外观品质性状中,白度与垩白粒率、垩白度、长宽比,垩白度与垩白粒率呈极显著正相关;长宽比与垩白粒率、垩白度呈极显著负相关;食味品质性状中,蛋白质含量与脂肪酸值,直链淀粉含量与蛋白质含量、脂肪酸值呈极显著正相关。此外,粳稻其他不同品质性状之间也存在不同程度的相关性。

籼粳超级杂交稻育种技术创新与品种培育

【目的】针对籼粳亚种间杂种优势利用存在的生育期偏长、结实率偏低、制种产量较低等问题,开展籼粳亚种间超级杂交稻育种技术创新与实践。【方法】通过籼粳渐渗杂交,选育花时早、柱头外露高的粳型保持系,进一步转育高异交率粳型不育系。通过籼粳渐渗杂交、广亲和基因分子标记辅助选择、籼粳成分定向选择等技术手段,选育穗型大、茎秆粗壮、广亲和性好、恢复谱广的籼粳中间型广亲和恢复系,并比较与普通粳稻恢复系在主要农艺性状、程氏指数、广亲和特性、广亲和基因、恢复谱等方面的差异。采用"粳不籼恢"和"籼不粳恢"2种配组方式,比较两者的光温反应类型表现与异交结实率差异。利用粳型不育系春江16A、籼型不育系五丰A与CH58、C84、C927等籼粳中间型广亲和恢复系配组,选育"粳不籼恢"或"籼不粳恢"籼粳亚种间杂交稻。【结果】在高异交率粳型不育系创制方面,转育出早花时粳型不育系春江16A以及春江99A、春江23A等早花时、高柱头外露率粳型不育系,制种产量明显提高;在籼粳中间型广亲和恢复系创新方面,选育出CH58、C84、C927等穗型大、茎秆粗壮、广亲和性好、恢复谱广的籼粳中间型广亲和恢复系。晚粳不育系/籼粳中间型广亲和恢复系的杂种一代表现为较强的感光特性,中粳不育系/籼粳中间型广亲和恢复系的杂种一代表现为感温特性,早籼不育系/籼粳中间型广亲和恢复系的杂种一代光温反应类型则表现不一。无论是"粳不籼恢"还是"籼不粳恢"配组,父母本的花时差小、不育系柱头外露率高,则有利于提高制种的异交结实率。采用"粳不籼恢"和"籼不粳恢"的配组方式,利用粳型不育系春江16A、籼型不育系五丰A与C84等籼粳中间型广亲和恢复系配组,选育出春优84、五优84等籼粳亚种间杂交稻并通过品种审定,表现出穗型大、杂种优势强、增产潜力大、抗倒性强、结实率高、后期耐寒性好等优点。【结论】通过籼粳渐渗杂交,成功转育出花时早、柱头外露率高的高异交率粳型不育系。籼粳中间型广亲和恢复系携带有S5-n,恢复谱广,明显不同于普通粳稻恢复系。中粳不育系/籼粳中间型广亲和恢复系的杂种一代表现为感温特性,有利于缩短全生育期。不育系柱头外露率高、父母本的花时差小,有利于提高籼粳亚种间杂交稻制种的异交结实率;选育出春优84等籼粳超级杂交稻组合。

籼粳交DH群体和RIL群体的构建及籼粳分化

对籼粳杂交组合“0 2 42 8(粳 ) /特青 (籼 )”F1 进行一步成苗法花药培养 ,对该组合的分离世代采用连续自交随机选择 ,分别获得由 132个株系组成的加倍单倍体 (DH)群体和由 15 7个株系组成的重组自交系 (RIL )群体。通过形态指数法和分子标记法对两个群体的籼粳分化进行了研究 ,结果表明 ,无论是 DH群体还是 RIL群体 ,各株系的籼粳形态指数和分子标记指数分布均呈正态分布 ,但 RIL群体的偏态性强于 DH群体 。

两系杂交稻优势生态型的初步研究

研究了培矮６４Ｓ和Ｎ４２２Ｓ与粳亚种中的东北粳、华北粳、日韩粳、云贵粳、非洲粳、美国稻及籼亚种中的云贵籼、太湖籼、华中籼和Ａｕｓ稻的杂种Ｆ１的产量及产量构成因素的杂种优势，初步确定美国稻、非洲粳、云贵粳以及华北粳中的改良品种是粳稻的优势生态型，太湖籼与云贵籼是籼稻的优势生态型。对籼粳优势生态型的产量优势进行比较发现，Ｎ４２２Ｓ／太湖籼低于Ｎ４２２Ｓ／美国稻，但与Ｎ４２２Ｓ／非洲粳和Ｎ４２２Ｓ／云贵粳相当；培矮６４Ｓ与粳稻优势生态型的优势强于与籼稻优势生态型的优势。两个不育系的优势比较表明，培矮６４Ｓ与各生态型的杂种优势强于Ｎ４２２Ｓ与各生态型的杂种优势。

经基因工程改良的抗白叶枯病水稻粳型恢复系“C418-Xa21”及其杂交稻

通过农杆菌介导的转化系统 ,将业已克隆的水稻抗白叶枯病基因Xa2 1导入重要的粳型杂交稻恢复系“C418”。PCR和抗性分析表明单拷贝整合的Xa2 1在T1 代的分离比为 3∶1。在T2 代通过PCR和抗性分析选择了Xa2 1纯合的转基因株系“C418 Xa2 1”。将选择的转基因纯合系“C418 Xa2 1”与常用的雄性不育系“屉锦A”杂交 ,产生了带有转基因Xa2 1的杂交稻“屉优 418 Xa2 1”(简称转基因杂交稻 )。分子分析表明转基因Xa2 1在杂交稻“屉优418 Xa2 1”中能稳定遗传 ;抗性分析表明转基因恢复系“C418 Xa2 1”和转基因杂交稻“屉优 418 Xa2 1”对白叶枯病具有高度的广谱抗性 ,并保持了受体对照的优良农艺性状。另外我们还发现转基因杂交稻“屉优 418 Xa2 1”对白叶枯病的抗性水平高于转基因恢复系“C418 Xa2 1” ,这可能是遗传背景的差异所致。抗白叶枯病转基因粳型恢复系和杂交稻的育成将有益于杂交稻在我国北方稻区的推广。

滇型杂交粳稻保持系与不育系柱头外露的遗传关系

通过对滇型杂交粳稻保持系和不育系开花期柱头外露率的调查,研究保持系与不育系柱头外露的遗传关系。分析结果表明:保持系柱头单外露率、双外露率与不育系柱头单外露率、双外露率均存在着极显著正相关关系,保持系柱头单外露率与不育系柱头单外露率之间的相关关系最密切;偏相关系数分别为rBA,A1=0.657,rB1A1,A=0.556,rB1A,A1=0.345,rBA1,A=0.100。保持系柱头单外露率、双外露率对不育系柱头单外露率的二元回归方程为:Y=2.623+0.765X1+0.455X2,说明保持系与不育系的柱头外露存在着显著的遗传关系。保持系柱头单外露率对不育系柱头单外露率的贡献(0.660)大于保持系柱头双外露率对不育系柱头单外露率的贡献(0.183),选择柱头外露率高的保持系能够选育出柱头外露率高的不育系。